mandela is undergoing tests. officials aren't saying why he's in the hospital. he is 94 years old. >>> two colorado university students are facing felony charges after police say they gave brownies laced with marijuana to their history class. authorities say the professor and another student had to be taken to the hospital. six others were treated at the school. again, not funny. >>> it's a welcome gift for drivers. plunging gas prices for the holidays. cnbc's mandy drurry is here with what's moving your money. how low can they go? >> hopefully, chris, 3 bucks a gallon in much of the country. at this stage you've got u.s. supplies rising. demand is not so hot. so what we're seeing, chris, is wholesale prices are sinking. and that is soon going to be reflected at the pump. we're averaging now around, what, $3.35 a gallon nationwide. prices are expected to drop to around $3.20 a gallon within the next two to three weeks. as you say, a welcome holiday gift for many. >> yeah. as gas prices are going down, business is going up for fedex. of course, always this time o